The Valve Job Postings Page has a listing for an Engineer Electronics Engineer that seems a pretty concrete confirmation of hot rumors that Valve is planning to develop hardware of some sort (thanks Engadget). Here's the introduction with the pertinent information speaking of "whole new gaming experiences.":

For years, Valve has been all about writing software that provides great gameplay experiences. Now we’re developing hardware to enhance those experiences, and you can be a key part of making that happen. Join our highly motivated team that’s doing hardware design, prototyping, testing, and production across a wide range of platforms. We’re not talking about me-too mice and gamepads here – help us invent whole new gaming experiences.

Sepharo wrote on Apr 13, 2012, 19:43:This falls into Dev's mantra too, because if Valve is "interested" in wearable-computing then that's what they're working on.

they could also be intentionally misleading competitors. we really wont know until they reveal something at E3 maybe?

I don't think valve has any history of that. They pretty much tell it like it is. They don't care much about competitors. To be honest, they don't really have any anyway. So far EA is intent on shooting themselves in the foot. Stardock sold impulse to gamestop. I hardly hear anymore about d2d (that used to be the main competitor to steam). GoG is mostly for older games. Desura is interesting, they are doing alpha drives for indies, but I don't think they are close to being a steam competitor.

Edit: I didn't even remember that gamefly bought out d2d a few months back until I googled to see what they were up to nowadays lol.